Hydraulically actuated grapple



1966 E. R. JOHNSON ETAVL 9 HYDRAULICALLY ACTUATED GRAPPIJE Filed May 24,1965 M? l3 l0 FIG. I

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|2 INVENTORS FIG. 2 w P M H ELWOOD R. JOHNSON 1 BY MERRITT DOWNING MJJMMUnited States Patent 3,294,435 HYDRAULICALLY ACTUATED GRAPPLE Elwood R.Johnson, Erie, and Merritt Downing, Fairview, Pa, assignors to EricStrayer Company, Erie, Pa., a corporation of Pennsylvania Filed May 24,1965, Ser. No. 458,017 7 Claims. (Cl. 29488) This invention relates tograpples and, more particularly, to hydraulic-electric operatedgrapples.

It is an object of this invention to provide an improvedhydraulicelectric grapple.

Another object of the invention is to provide a grapple having an oiltank built thereinto and having jaws swingably mounted to the oil tankand connected to a support member by means of links with hydraulicallyactuated cylinders connected between the oil tank and the support and apump and motor supported on the oil tank for supplying oil underpressure to the cylinders.

A further object of the invention is to provide a grapple which issimple in construction, economical to manufacture, and simple andefficient in operation.

With the above and other objects in view, the present invention consistsof the combination and arrangement of parts hereinafter more fullydescribed, illustrated in the accompanying drawing and more particularlypointed out in the appended claims, it being understood that changes maybe made in the form, size, proportions, and minor details ofconstruction without departing from the spirit or sacrificing any of theadvantages of the invention.

In the drawing:

FIG. 1 is an isometric view of a grapple according to the invention; andI FIG. 2 is a view of the hydraulic circuit for operating the grapple.

Now with more particular reference to the drawing, the grapple is shownat 10 having jaws 27 which are four in number in the example shown andwhich are swingably supported to an oil tank 13 by means of pins 28. Thepins 28 extend through cars 29 which are integrally attached to the oiltank through openings in the ends of the jaws 27 which are remote frompoints 30.

The oil tank 13 has a flat top with frame which supports the motor 11and pump 12. The cylinders 14 are attached at their lower ends to thetop of the oil tank. The cylinders have pistons therein with piston rodswhich are connected at their upper ends to the upper support 25. Thespaced links 26 are each made of two parts which are arranged parallelto each other and attached to each other by means of truss members 31.The upper ends of the links 26 are pivotally connected to the uppersupport by means of pins 32 which pass through the ears 33 and throughthe spacers 34 which are located between the upper ends of the links.

The hydraulic circuit is made up of the two pistons supported in thecylinders 14. The cylinders are double acting and their lower ends areconnected as shown in FIG. 2 to the four-way valve 35. The four-wayvalve 35 may be pushed to one position by an electrically actuatedsolenoid 16 which will direct hydraulic fluid from the tank 13 through afilter 23 and into the pump 12. The pump 12 will direct the fluid to thecheck valve 18 to the space in the cylinders 14- above the hydraulicpistons, causing the jaws 27 to close. The cylinders will remain in theposition they are in when the valve is moved to the neutral position.

When the solenoid 15 is actuated, the flow of oil from the valve 35 willbe reversed and it will cause the pistons to be extended in thecylinders. The pressure relief control 17 with a gauge is provided toregulate the maximum pressure of the system. A solenoid valve 24 isprovided in parallel with the pressure relief control to add greaterflexibility of the control and to relieve the pump 12 from working underfull pressure in the neutral position as shown.

A suitable orifice 19 and check valve 20 are provided in the circuit sothat the jaws will open slower but close faster. The check valve willstop the oil from passing from the space above the cylinders but the oilcan still flow through the orifice 19 so that the cylinders will openslower. This feature is well known in other hydraulic circuits.

The jaws are opened and closed by cylinders 14. Fluid is supplied foropening and closing by valve 35.

A regenerative circuit made up of the valve 35 which removes oil fromabove the piston and replaces below it in cylinders 14 would normallyopen the grab too fast. Therefore, fiow control 19 is provided whichreduces the rate of flow of fluid to the bottom parts of the cylinders14. Thus, the grab will open in less time than its closing time, yet notas fast as it would but for flow control 19.

A suitable accumulator 21 is provided and a vent 22 for the oil tank.The upper support 25 has a suspension eye 36 thereon which may beattached to a suitable hoist line on a crane or the like.

It will be readily apparent to those skilled in the art that when oil isdriven in one direction to the space below the pistons in the cylindersby the pump 12, the pistons will be extended and the bucket will beopened. When oil is driven into the space above the pistons, they willretract and the jaws will close.

The foregoing specification sets forth the invention in its preferredpractical forms but it is understood that the structure shown is capableof modification within a range of equivalents without departing from theinvention which is to be understood is broadly novel as is commensuratewith the appended claims.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. A grapple comprising an oil tank,

spaced jaws swingably attcahed to said oil tank and having a pointspaced from said oil tank,

an upper support,

spaced links having an upper and a lower end,

the upper end of each said spaced link being swingably connected to saidupper support,

the lower end of each said spaced link being swingably attached to asaid spaced jaw between said oil tank and said point,

spaced hydraulic cylinders,

each said hydraulic cylinder being attached to said oil tank,

a piston in each said hydraulic cylinder having a piston rod attachedthereto,

each said piston rod being attached to said upper support,

a pump supported on said oil tank between said links and said uppersupport,

motor means connected to said pump,

and hydraulic pipe means connecting said pump to said oil tank and tosaid hydraulic cylinders. 2. The grapple recited in claim 1 whereinvalve means is provided in said hydraulic pipe means, said valve meanscomprises a reversing valve having a neutral position,

means to move actuating means on said reversing valve to a firstposition to move said pistons in a first direction to open said jaws,

and means to move actuating means on said reversing valve to a secondposition to close said jaws.

3. The grapple recited in claim 1 wherein means is attached to saidsupport for attaching a hoist and two said link members are attached toeach side of line thereto. said rectangular support at spaced positionsthereon.

4. The grapple recited in claim 1 wherein The p e recited in claim} 1wherein four said jaws are provided, at least two said aws are provided,

id v il k h fo r sides, 5 said oil tank has sides to accommodate saidjaws,

one end of each jaw is swingably connected to a said of each sa1( 1 Jaw15 swmgably connected to a side f Said oil tank said side of said 011tank,

Said upper Support is rectangular sa1d upper support is 1n the shape of-a regular polygon,

one end of each said link is connected to a side of said upper support,and another end of each said link is connected to an one end of eachsaid link is connected to a side of said upper support,

and another end of each said link is connected to an i di pal-t f a id jintermediate part of said jaw.

5. The grapple recited in claim 4 wherein References Cited y theExamine! a each said link is made of two spaced link members, 15 UNITEDSTATES PATENTS truss means connecting said link members, 2,501,594 1 5Billings 7 1 7 each said link being connected to a'said jaw and to said2,877,575 3/1959 St dt 294, 88 X upper support at a position spaced fromthe other.

6. The grapple recited in claim 5 wherein GERALD FORLENZA: PfimmyExamine"- said upper support is rectangular, G. F. ABRAHAM, AssistantExaminer.

1. A GRAPPLE COMPRISING AN OIL TANK, SPACED JAWS SWINGABLY ATTACHED TOSAID OIL TANK AND HAVING A POINT SPACED FROM SAID OL TANK, AN UPPERSUPPORT, SPACED LINKS HAVING AN UPPER AND A LOWER END, THE UPPER END OFEACH OF SAID SPACED LINK BEING SWINGABLY CONNECTED TO SAID UPPERSUPPORT, THE LOWER END OF EACH SAID SPACED LINK BEING SWINGABLY ATTACHEDTO A SAID SPACED JAW BETWEEN SAID OIL TANK AND SAID POINT, SPACEDHYDRAULIC CYLINDERS, EACH SAID HYDRAULIC CYLINDER BEING ATTACHED TO SAIDOIL TANK, A PISTON IN EACH SAID HYDRAULIC CYLINDER HAVING A PISTON RODATTACHED THERETO, EACH SAID PISTON ROD BEING ATTACHED TO SAID UPPERSUPPORT, A PUMP SUPPORTED ON SAID OIL TANK BETWEEN SAID LINKS AND SAIDUPPER SUPPORT, MOTOR MEANS CONNECTED TO SAID PUMP, AND HYDRAULIC PIPEMEANS CONNECTING SAID PUMP TO SAID OIL TANK AND TO SAID HYDRAULICCYLINDERS.